1. Field of the Invention
The present invention relates to a safety photoelectric switch.
2. Description of the Background Art
As seen in Japanese Patent Application Laid-Open No. H4-310890 and Japanese Patent Application Laid-Open No. H3-175390, an optical scanning type photoelectric switch is known which two-dimensionally performs scanning with light to detect an object while detecting a position of this object. As also referred to as a safety scanner, a safety laser scanner, and the like, this optical scanning type photoelectric switch provides a protection area around a machine, a robot or the like as a danger source, and outputs to the danger source a safety signal not permitting its operation when an operator or the like enters this protection area.
A detection sensitivity of the optical scanning type photoelectric switch is decided based upon a light projection intensity or a light reception intensity, and on top of this, as shown in Japanese Patent Application Laid-Open No. H3-175390, when a mirror for polarizing light is provided inside the optical scanning type photoelectric switch, the detection sensitivity of the optical scanning type photoelectric switch is decided based upon optical characteristics of a lens for collecting light and a scanning mirror for performing scanning with light.